Batch, semi-batch or continuous processes are established for the emulsion polymerization of ethylenically unsaturated monomers. Batch or semi-batch processes are carried out usually in stirred reactors, and continuous processes in stirred tank cascades, tubular reactors or loop reactors. Thus, for example, DE 2555142 describes continuous processes for the emulsion polymerization of ethylenically unsaturated monomers in a plurality of serially connected polymerization reactors. WO 02/59158 teaches polymerization in reactors having an external cooling circuit, in which the polymerization mixture is pumped in a circuit, and at least a portion of the monomers are metered into the external circuit. When being pumped, dispersed polymer particles exhibit a tendency towards coagulation, owing to the shearing forces they experience in the process, and this is a factor especially in the case of high-volume mixtures.
For the continuous bulk polymerization of ethylenically unsaturated monomers, US 2005/0159565 and US 2006/0062702 recommend Taylor reactors, whose reactor chamber widens the reactor entry towards the reactor exit. US 2006/0204406 proposes similar Taylor reactors for the solution polymerization of ethylenically unsaturated monomers. DE 10150483 discloses the use of Taylor reactors for the preparation of poly(meth)acrylates by emulsion polymerization in the presence of emulsifiers. EP 2471594 describes Taylor reactors equipped with wipers or scrapers for producing synthetic rubbers by polymerization in organic solvents.
WO 00/00280 teaches Taylor reactors with specific reactor volume geometry, and recommends such reactors for a wide variety of different, end-use applications—for example, for polymer-analogous reactions, production of polyurethane resins or polyureas, or else for polymerization of a wide variety of different ethylenically unsaturated monomers in solution. DE 19960389 as well recommends similar Taylor reactors for a wide variety of different polymer technologies. EP 0498583 describes Taylor reactors for the emulsion polymerization of a wide variety of different ethylenically unsaturated monomers.